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Integration of environmental, agronomic, and economic aspects of fertilizer management 总被引:5,自引:0,他引:5
Nitrogen fertilization is a substantial source of nitrogen-containing trace gases that have both regional and global consequences. In the intensive wheat systems of Mexico, typical fertilization practices lead to extremely high fluxes of nitrous oxide (N2O) and nitric oxide (NO). In experiments, lower rates of nitrogen fertilizer, applied later in the crop cycle, reduced the loss of nitrogen without affecting yield and grain quality. Economic analyses projected this alternative practice to save 12 to 17 percent of after-tax profits. A knowledge-intensive approach to fertilizer management can substitute for higher levels of inputs, saving farmers money and reducing environmental costs. 相似文献
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Inherited diseases of Australian Holstein-Friesian cattle 总被引:1,自引:1,他引:0
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An outbreak of intestinal coccidiosis in the dog due to Isospora canis characterized by mild severe haemorrhagic diarrhoea of sudden onset, acute abdominal pain, anorexia, dehydration and relative polycythaemia is described. Although clinical recovery followed sulphonamide therapy, reinfection was common within 10 days of treatment. 相似文献
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The results of a tobacco smoking survey conducted among veterinarians in Queensland, Australia, during 2007 are presented. Of the 567 participants only 3% reported being current smokers, 24% were ex-smokers and 73% had never smoked. The prevalence of smoking was similar among males and females, and the highest smoking rate was reported among veterinarians aged 31–40 years. However, the rate of never-smokers was strongly and negatively correlated with age, and the proportion of ex-smokers increased with age. Encouragingly, the results from this study suggest that tobacco use has all but disappeared from the Australian veterinary profession in recent years. 相似文献
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